Our UV slit lamp densitography approach will enable us to measure at least two lens fluorescence parameters in vivo. We will screen patients and monitor their age-related lens fluorescence levels utilizing a reproducible objective method which can determine normal fluorescence according to age group and abnormal elevations. These data should provide information about molecular changes in the lens months to years before they might become manifest by conventional slit lamp examination. UV slit lamp densitography could prove useful in monitoring patients on phototherapy and/or individuals whose occupation exposes them to higher than ambient levels of UV radiation. Aside from its use in cataract classification, screening and prevention programs, UV slit lamp densitography can measure the UV filtering capacity of the lens and provide objective data which could help answer the question regarding the role of long wave UV radiation photodamage in retinal degenerative disease processes. Our in vitro photobiologic studies have enabled us to define at least two of the densitography peaks and assign them to the 440 and 520 nm fluorescence emission wavelengths determined by whole lens fluorescence spectroscopy. We will further investigate the potential hazard of retinal photodamage in children and in aphakes associated with photosensitizing agents. Additional evidence has accumulated indicating that photodamage can affect and be associated with corneal aging and certain dystrophies. UV densitography will be employed to monitor in vivo enhanced corneal fluorescence with age which correlates with our in vitro observations. Our studies on lens transparency, aging and opacification will utilize NMR spectroscopy to analyze the phase separation phenomenon in intact young rat, rabbit and human lenses and on protein solutions extracted from these lenses. Preliminary experiments are compatible with a phase transition phenomenon in young lenses which be associated with certain proteins within the lens.